Methods and apparatus have been developed for generating three-dimensional photographs. One such system utilizes a camera with a film mount therein, a line raster, a film and a separator for keeping the line raster separated from the film. A vacuum generating device maintains a vacuum in the vicinity of the separator. This brings the film into intimate contact with the separator and maintains the intimate contact through successive exposures and movement of the film and line raster. After repeated exposure of the film in various positions with respect to the subject being photographed, the exposed film is removed and developed. The developed film and a raster are again assembled on a separator. The resulting photograph is viewed from the raster side of the assembly by means of a light source and a diffusion screen behind the film side of the assembly. This system is disclosed in detail in U.S. patent application Ser. No. 417,855, now U.S. Pat. No. 4,481,050, filed Sept. 14, 1982, for Gundlach et al and entitled IMPROVED METHOD OF MAKING A THREE-DIMENSIONAL PHOTOGRAPH AND PHOTOGRAPH RESULTING THEREFROM.
The apparatus employed in the above noted U.S. patent application employs full size equipment. That is, the original film which is exposed and developed is the same size as the three dimensional photographic print to be exhibited or viewed. The original developed film is employed as the first generation print to be viewed and is a free vision multi exposed single photograph being viewed with the naked eye. The process as described in the above noted application employs a dimensionally stable film having a low ASA rating, for example Ilford Cibachrome II CTD. 7 transparent film with a 0.18 millimeter transparent polyester base. The ASA rating of the Cibachrome II transparent film is about 1/54 of an ASA unit.
U.S. Pat. No. 3,560,296 for METHOD FOR PREPARING 3-DIMENSIONAL PICTURES relates to making lenticular screen stereographs. The apparatus for making these stereographs includes using a filmstrip with color separation and an enlarger in conjunction with a film sandwich. In the system disclosed in the patent, a stationary lenticular screen with a raster is used to enhance the lens quality of the lenticular screen. A film is located behind the lenticular screen and is advanced in increments in the order of one lenticular element (column 4, lines 47-75). In operation of the system, in each exposure, the film is moved transversely a minute distance measured in terms of a fraction of a width of one lenticule with respect to the screen as each transparency is projected through the projector (column 7, lines 18-35).
U.S. Pat. No. 4,158,501 for PROJECTION PRINTION METHOD AND APPARATUS relates to the mass production of lenticular screen stereoscopic photographs. Mechanical and optical sensors align serially projected images through a line grid between subsequent exposures. The paper is processed and laminated to lenticular screen. The structure disclosed in the patent employs a raster which is moved relative to a film to be exposed. The movement, as with the previous structure noted above, involves minute movement. The exposure onto the film or photosensitive material is made employing a movable line grid. A lenticular lens is superimposed over the developed picture to form the photograph. In column 12 of the patent, it is noted that the line grid and paper are movable together in horizontal increments; however, this reference refers back to a reference in column 10 wherein it is noted that relative movement occurs between the line grid and the paper. Accordingly, it is believed that although the line grid and paper are moved together in horizontal increments, a relative movement continues to exist which may involve movement between the line grid and paper possibly at different speeds or in different directions.